Unless otherwise indicated, the materials described in the background section are not prior art to the claims in the present application and are not admitted to be prior art by inclusion in this section.
The yoyo is a toy which originated with the ancient Greek and is more than 2400 years in use. In its simplest form, the yoyo consists of an axle connected to two disks, and a length of string looped around the axle, similar to a slender spool. It is played by holding the free end of the string known as the handle (usually by inserting one finger in a slip knot) allowing gravity or the force of a throw to spin the yoyo and unwind the string, then allowing the yoyo to wind itself back to one's hand, exploiting its spin and the associated rotational energy.
Many inventions exist which minimize the friction between the axle and the string. Lower friction results in the ability for the yoyo to spin freely while the string is completely unwound. Softly touching the yoyo to the ground while it is thus spinning creates a forward or reverse motion for the yoyo and is a common trick with the yoyo.
The subject matter claimed herein is not limited to embodiments that solve any disadvantages or that operate only in environments such as those described above. Rather, this background is only provided to illustrate one exemplary technology area where some embodiments described herein may be practiced.